hi guys ive had a shocker with the 1200 lately it snapped all of the flywheel bolts off before i had even made it to turn 2 at wakefield and its ruined the flywheel but not the crakn luckily. i have an a12 out of a vanette and just want to know if those flywheels could be the same or is the a15 one different?
cheers kurt

Yes they are different

1. A15 flywheel is heavier

2. Flywheel bolts differ by year
1966-1973 use imperial threads
1974-2007 use metric threads

being from an A12 powered van, I would dare say that it would be of the heavier variety.

What a pisser! Woodie, the A12 flywheel should be lighter, thinner & in my opinion safer to lighten, as the A15 flywhels have a big void in the back of them. What setting did you torque the bolts to? Its not a knife edged crank, is it? The only time I've had flywheel bolts break was when I drove a friends Toyota & revved it like my Datsun. I'd chuck both flywheels on some bathroom scales to see which one was lighter, & also check the bolt holes to see if they're not ovaled. Or just get an SR20 like you wanted & make it a 2 litre.

good idea with the bathroom scales, are the number of teeth different between them? and the bolt spacing ill just have to check that, its definatly a metric thread because i had to tap one out when i put it on. hey paul, it wasnt reving that hard 6000 when i normally take it to 8000 and i had just changed gear. as for the sr20det idea i would really like too but ive bought a sports sedan, funny how most young people my age go and get a loan for the latest commodore or falcon, i got one for a racecar lol

I have compared the flywheel of my A15 with my A12 and the results are

A15 flywheel = 9,8Kg
A12 flywheel = 9,4Kg

Yes, they use the same bolt spacing and gear teeth.

Imperial bolts fit tight, if you had to tap them out they may be imperial instead of metric. Pre-1974 engines used imperial flywheel bolts.

Not to imply anything, Woodie, but the only other time I saw something like this happen was when the a friends son forgot to torque the flywheel bolts on his A15. Thats why I asked about what you torqued them to. The Toyota I broke the bolts in was a Corolla with I think a 2S, or maybe an 18RG. They didn't tell me not to rev it past 6000 rpm or not do static linklockers, so It's not my fault. Actually it was & I had to pay for a new flywheel & ARP flywheel bolts, as the crank was ok. Can't suggest why the bolts would break at 6000 rpm unless they weren't tight.

thanks for the weights gandalf. dd i had to tap one out because it picked up some old loctite that carby clearner couldnt shift so i decided to screw the bolt in by hand and then it started cross threading halfway down the hole. and paul they are aftermarket bolts not arp or anything so i just did them up to FT and i couldnt find my tension wrench and just wanted it going last time i did them i did them up to 80ftlb with loctite. and im wondering if i have an engine balance issue, its been doing gearboxes left right and centre, the oil seals in the back and the bushes as well and a bad vibration through the whole car lately, i put it down to the tailshaft which is what the new gearbox setup was to test but that didnt last long.

Quote:This was the source of the problem. Yes, all four cylinder engines vibrate. This makes the flywheel bolt torque one of the most critical on the whole car. If they are not exact even, one will start to work loose eventually. If they are not at the specified tightness, they will get loose. If they are too tight, the bolts are weakened. Lesson learned, never skip the torque wrench when it comes to internal engine bolts.